As with other extendable deadline tasks, "File Statement of Use" tasks should ONLY be marked complete if the statement of use was actually filed before the deadline. Specifically, the task is for filing the statement itself, not filing an extension of time. If you filed for an extension of time instead, mark the "File Statement of Use" task as Missed or Filed Extension. This will close the task and, importantly, generate the next extension. 

For example, a "File Statement of Use - 6 month deadline" task is due on 1/1/16. If the actual statement of use is filed before or on 1/1/6, marked the task as 'completed.' If an extension of time was filed instead, mark the task as 'Missed' or 'Filed Extension'. This will remove the 6 month deadline from the docket and create a "File Statement of Use - 12 month Deadline" task with a 7/1/16 due date.